1. Field of the Invention
The present invention relates to a bearing device for rotatably supporting a shaft used for connecting a cover to a main body.
2. Description of the Related Art
In an OA device such as a word processor 60, a display 46 is mounted to a keyboard 16 so as to be openable and closable. Thus, the display 46 can be compactly folded when not in use (see FIG. 4). A torque resistant to rotation is applied to a hinged portion provided between the keyboard 16 and the display 46 so that the speed at which the display 46 is opened or closed is kept constant so there is no shock to the display 46.
As a mechanism for developing such a resisting torque in the hinged portion, there has generally been known a structure shown in FIGS. 5 and 6.
Described specifically, a holder 62 is mounted to the keyboard 16 and a shaft 68 fixed to the display 46 is supported by a shaft hole 66 defined in a shaft plate 64 mounted to the holder 62. A leaf spring 74 is made tight or caulked so as to be mounted on a small-diameter portion 68A of the shaft 68 which is extending through the shaft hole 66 with the leaf spring 74 interposed between spacers 70 and 72. A torque resistant to the rotation of the shaft 68 is developed by a frictional force produced between an end face 68B of the shaft 68 and a side surface of the shaft plate 64 or between the side surface of the shaft plate 64 and the spacer 70 under the action of an urging force developed by elastic deformations of concave and convex portions of the leaf spring 74.
In such a torque producing mechanism, however, the caulked portion is loosened when the number of times in which the display is opened and closed increases, so that a stable resisting torque cannot be produced. Since the number of parts increases, the work of mounting the torque producing mechanism become cumbersome. It is also difficult to reduce the manufacturing cost.